Dual texture absorbent nonwoven web

ABSTRACT

A dual texture coform nonwoven web prepared from meltblown filaments and at least one secondary material is disclosed. The dual texture coform nonwoven web is useful as cleaning pads, wipes, mops, among other articles of manufacture. One surface of the dual texture coform nonwoven web contains coarse filaments, which impart an abrasive characteristic to this surface of the nonwoven web and the other surface contains fine filaments, which impart a non-abrasive or soft surface to the nonwoven web. Also disclosed is the process of producing the dual texture coform nonwoven web, method of using the dual texture coform nonwoven web as a wipe, mop, and the like, along with cleaning kits containing the coform nonwoven web.

FIELD OF THE INVENTION

[0001] The present invention relates to a dual texture coform nonwovenweb prepared from thermoplastic meltblown filaments and at least onesecondary material. The dual texture coform nonwoven web is useful ascleaning pads, wipes, and mops, among other articles of manufacture. Onesurface of the dual texture coform nonwoven web contains coarsemeltblown filaments, which impart an abrasive characteristic to thissurface of the nonwoven web, and the secondary material and the othersurface contains fine meltblown filaments, which impart a non-abrasiveor soft surface to the nonwoven web, and the secondary material. Thepresent invention also relates to a process of producing the dualtexture coform nonwoven web, a method of using the dual texture coformnonwoven web as a wipe, a mop and the like, along with cleaning kitscontaining the coform nonwoven web.

BACKGROUND OF THE INVENTION

[0002] Coform nonwoven webs or coform materials are known in the art andhave been used in a wide variety of applications, including wipes. Theterm “coform material” means a composite material containing a mixtureor stabilized matrix of thermoplastic filaments and at least oneadditional material, often called the “second material” or “secondarymaterial”. Examples of the second material include, for example,absorbent fibrous organic materials such as woody and non-wood pulpfrom, for example, cotton, rayon, recycled paper, pulp fluff;superabsorbent materials such as superabsorbent particles and fibers;inorganic absorbent materials and treated polymeric staple fibers, andother materials such as non-absorbent staple fibers and non-absorbentparticles and the like. Exemplary coform materials are disclosed incommonly assigned U.S. Pat. No. 5,350,624 to Georger et al.; U.S. Pat.No. 4,100,324 to Anderson et al. and U.S. Pat. No. 4,818,464 to Lau etal.

[0003] Dual texture nonwoven webs are also known in the art, and aredescribed in, for example, U.S. Pat. No. 4,659,609 to Lamers et al.,U.S. Pat. No. 5,639,541 to Adam, both of which are hereby incorporatedby reference in their entirety. In Lamers et al., a layered nonwoven webis formed, and this layered nonwoven has a layer of coarse fibersmeltblown onto a support substrate. The support substrate can be a widevariety of substrates, including substrates containing a combination ofpolymers and other fibers, such as cellulosic fibers. The coarse fibersof Lamers et al. have an average fiber diameter above 40 microns. Inaddition, the coarse fibers are in a separate layer of the layerednonwoven web and this coarse fiber layer does not contain a secondarymaterial. That is, the coarse fibers are used alone in the coarse layerof Lamers. In Adam, a layered meltblown nonwoven web is produced bylaying down layers of meltblown fibers, wherein at least one layercontains fine microfibers and at least one layer contains coarse fibers,having an average diameter between about 8 and 23 microns. The nonwovenweb of Adam is used as an abrasion resistant, oil absorbent mat. Thecoarse fibers of Adam improve the durability of the nonwoven web and,like Lamers et al., are in a separate layer from the other fibers of thenonwoven web.

[0004] Coform nonwoven webs have been used in applications such asdisposable absorbent articles, absorbent dry wipes, wet wipes, wet mopsand dry mops. However, the prior coform materials did not have anabrasive surface to provide a scrubbing or scouring ability to thenonwoven web, wherein abrasive fibers or coarse fiber were integratedinto secondary material.

[0005] There is a need in the art for a nonwoven web which can be usedin absorbent dry wipes, wet wipes and wet or dry mops which provide ascrubbing or scouring ability along with a soft surface for generalwiping, having an effective pick-up of dirt and debris.

SUMMARY OF THE INVENTION

[0006] The present invention provides a dual texture nonwoven web havinga matrix containing 1) thermoplastic meltblown filaments and 2) at leastone secondary material. The dual texture coform nonwoven web has a firstexterior surface and a second exterior surface, wherein the firstexterior surface has fine thermoplastic meltblown filaments having anaverage fiber diameter of less than about 15 microns and the secondarymaterial; and the second exterior surface has coarse thermoplasticmeltblown filaments having an average fiber diameter greater than about15 microns and the secondary material.

[0007] In further aspects of the present invention, the first and secondsurfaces may contain both the fine filaments and the coarse filaments.That is, the first surface and the second surface both contain a matrixcontaining coarse filaments, fine filaments and at least one secondarymaterial. In addition, the coarse filaments may be present is a gradientfashion, decreasing in weight percentage from the second surface towardsthe first surface.

[0008] The present invention also provides methods for producing thedual texture coform nonwoven web. One method for preparing a dualtexture coform nonwoven web has the steps of:

[0009] a. providing a first stream of thermoplastic meltblown filamentshaving an average diameter of less than about 15 microns;

[0010] b. providing a second stream of thermoplastic meltblown filamentshaving an average diameter greater than about 15 microns;

[0011] c. converging the first stream of thermoplastic meltblownfilaments and the second stream of thermoplastic meltblown filaments inan intersecting relationship to form an impingement zone;

[0012] d. introducing a stream containing at least one secondarymaterial between the first and second streams of the thermoplasticmeltblown filaments at or near the impingement zone to form a compositestream; and

[0013] e. depositing the composite stream onto a forming surface as amatrix of thermoplastic meltblown filaments and at least one secondarymaterial to form a nonwoven web containing a first and a second exteriorsurface; the first exterior surface contains fine thermoplasticmeltblown fibers having average diameter of less than about 15 micronsand the secondary material, and the second exterior surface containscoarse thermoplastic meltblown fibers having an average diameter greaterthan about 15 microns and the secondary material.

[0014] Another method for producing the coform nonwoven web of thepresent invention includes the steps of:

[0015] a. providing a first stream of thermoplastic meltblown filaments;

[0016] b. introducing a stream containing at least one secondarymaterial to the first stream of thermoplastic meltblown filaments toform a first composite stream;

[0017] c. providing a second stream of thermoplastic meltblownfilaments;

[0018] d. introducing a stream at least one secondary material to thesecond stream of meltblown filaments to form a second composite stream;

[0019] e. depositing the first composite stream onto a forming surfaceas a matrix of thermoplastic meltblown filaments and at least onesecondary material to form a first deposited layer; and

[0020] f. depositing the second composite stream onto the firstdeposited layer as a matrix of thermoplastic meltblown filaments and atleast one secondary material to form a dual texture coform nonwoven web;

[0021] wherein one of the first stream of thermoplastic meltblownfilaments or the second stream of thermoplastic meltblown filamentscontains thermoplastic meltblown filaments having average diameter ofless than about 15 microns and the other of the first stream ofthermoplastic meltblown fibers or the second stream of thermoplasticmeltblown fibers contains thermoplastic meltblown filaments having anaverage diameter greater than about 15 microns.

[0022] The dual texture coform nonwoven webs and laminates of thepresent invention are useful as dry wipes, absorbent wipes,pre-moistened wipes, dry mops, absorbent mops, pre-moistened mops, amongother absorbent articles of manufacture.

[0023] The present invention also relates to a cleaning implementcomprising a handle; a head; and a removable cleaning sheet; wherein thehead is connected to the handle and the removable cleaning sheet isremovably attached to the head. The cleaning sheet is prepared from thedual texture coform nonwoven web described above.

[0024] A further aspect of the present invention relates to a method ofcleaning a surface by contacting and wiping the surface with the dualtexture coform nonwoven web of the present invention.

[0025] The present invention also relates to a kit containing thecleaning implement of the present invention and a plurality of wipes ormops of the present invention.

[0026] In another aspect of the present invention, a stack of individualcoform nonwoven webs which are premoistened is also provided. The stackof webs can be used as wipes or mops and can be removed from a containerholding the stack of the material one or more at a time.

BRIEF DESCRIPTIONS OF THE DRAWINGS

[0027]FIG. 1 illustrates a process which can be used to prepare the dualtexture nonwoven web of the present invention.

[0028]FIG. 2 illustrates a second process which may be used to prepare adual texture coform nonwoven web laminate of the present invention.

[0029]FIG. 3 illustrates a cleaning implement of the present invention.

[0030]FIG. 4 is a micrograph of the structure of a dual texture coformnonwoven web of the present invention.

DEFINITIONS

[0031] As used herein, the term “comprising” is inclusive or open-endedand does not exclude additional unrecited elements, compositionalcomponents, or method steps.

[0032] As used herein, the term “fiber” includes both staple fibers,i.e., fibers which have a defined length between about 2 and about 20mm, fibers longer than staple fiber but are not continuous, andcontinuous fibers, which are sometimes called “substantially continuousfilaments” or simply “filaments”. The method in which the fiber isprepared will determine if the fiber is a staple fiber or a continuousfilament.

[0033] As used herein, the term “nonwoven web” means a web having astructure of individual fibers or threads which are interlaid, but notin an identifiable manner as in a knitted web. Nonwoven webs have beenformed from many processes, such as, for example, meltblowing processes,spunbonding processes, air-laying processes, coforming processes andbonded carded web processes. The basis weight of nonwoven webs isusually expressed in ounces of material per square yard (osy) or gramsper square meter (gsm) and the fiber diameters useful are usuallyexpressed in microns, or in the case of staple fibers, denier. It isnoted that to convert from osy to gsm, multiply osy by 33.91.

[0034] As used herein, the term “meltblown fibers” means fibers formedby extruding a molten thermoplastic material through a plurality offine, usually circular, die capillaries as molten threads or filamentsinto converging high velocity, usually hot, gas (e.g. air) streams whichattenuate the filaments of molten thermoplastic material to reduce theirdiameter, which may be to microfiber diameter. Thereafter, the meltblownfibers are carried by the high velocity gas stream and are deposited ona collecting surface to form a web of randomly dispersed meltblownfibers. Such a process is disclosed, for example, in U.S. Pat. No.3,849,241 to Butin, which is hereby incorporated by reference in itsentirety. Meltblown fibers are microfibers, which may be continuous ordiscontinuous, and are generally smaller than 10 microns in averagediameter, and are generally tacky when deposited onto a collectingsurface.

[0035] As used herein, the term “coform nonwoven web” or “coformmaterial” means composite materials comprising a mixture or stabilizedmatrix of thermoplastic filaments and at least one additional material,usually called the “second material” or the “secondary material”. As anexample, coform materials may be made by a process in which at least onemeltblown die head is arranged near a chute through which the secondmaterial is added to the web while it is forming. The second materialmay be, for example, an absorbent material such as fibrous organicmaterials such as woody and non-wood pulp such as cotton, rayon,recycled paper, pulp fluff; superabsorbent materials such assuperabsorbent particles and fibers; inorganic absorbent materials andtreated polymeric staple fibers and the like; or a non-absorbentmaterial, such as non-absorbent staple fibers or non-absorbentparticles. Exemplary coform materials are disclosed in commonly assignedU.S. Pat. No. 5,350,624 to Georger et al.; U.S. Pat. No. 4,100,324 toAnderson et al.; and U.S. Pat. No. 4,818,464 to Lau et al, U.S. Pat. No.5,720,832 to Minto et al.; the entire contents of each is herebyincorporated by reference. In addition, coform material containingsuperabsorbent particles is disclosed in U.S. Pat. No. 4,429,001 toKoplin, also hereby incorporated in its entirety.

[0036] As used herein the term “spunbond fibers” refers to smalldiameter fibers of molecularly oriented polymeric material. Spunbondfibers may be formed by extruding molten thermoplastic material asfilaments from a plurality of fine, usually circular capillaries of aspinneret with the diameter of the extruded filaments then being rapidlyreduced as in, for example, U.S. Pat. No. 4,340,563 to Appel et al., andU.S. Pat. No. 3,692,618 to Dorschner et al., U.S. Pat. No. 3,802,817 toMatsuki et al., U.S. Pat. Nos. 3,338,992 and 3,341,394 to Kinney, U.S.Pat. No. 3,502,763 to Hartman, U.S. Pat. No. 3,542,615 to Dobo et al,and U.S. Pat. No. 5,382,400 to Pike et al. Spunbond fibers are generallynot tacky when they are deposited onto a collecting surface and aregenerally continuous. Spunbond fibers are often about 10 microns orgreater in diameter. However, fine fiber spunbond webs (having anaverage fiber diameter less than about 10 microns) may be achieved byvarious methods including, but not limited to, those described incommonly assigned U.S. Pat. No. 6,200,669 to Marmon et al. and U.S. Pat.No. 5,759,926 to Pike et al.

[0037] As used herein, the term “polymer” generally includes, but is notlimited to, homopolymers, copolymers, such as for example, block, graft,random and alternating copolymers, terpolymers, etc. and blends andmodifications thereof. Furthermore, unless otherwise specificallylimited, the term “polymer” shall include all possible geometricalconfigurations of the molecule. These configurations include, but arenot limited to isotactic, syndiotactic and random symmetries.

[0038] As used herein, the term “multicomponent fibers” refers to fibersor filaments which have been formed from at least two polymers extrudedfrom separate extruders but spun together to form one fiber.Multicomponent fibers are also sometimes referred to as “conjugate” or“bicomponent” fibers or filaments. The term “bicomponent” means thatthere are two polymeric components making up the fibers. The polymersare usually different from each other, although conjugate fibers may beprepared from the same polymer, if the polymer in each component isdifferent from one another in some physical property, such as, forexample, melting point or the softening point. In all cases, thepolymers are arranged in substantially constantly positioned distinctzones across the cross-section of the multicomponent fibers or filamentsand extend continuously along the length of the multicomponent fibers orfilaments. The configuration of such a multicomponent fiber may be, forexample, a sheath/core arrangement, wherein one polymer is surrounded byanother, a side-by-side arrangement, a pie arrangement or an“islands-in-the-sea” arrangement. Multicomponent fibers are taught inU.S. Pat. No. 5,108,820 to Kaneko et al.; U.S. Pat. No. 5,336,552 toStrack et al.; and U.S. Pat. No. 5,382,400 to Pike et al.; the entirecontent of each is incorporated herein by reference. For two componentfibers or filaments, the polymers may be present in ratios of 75/25,50/50, 25/75 or any other desired ratios.

[0039] As used herein, the term “multiconstituent fibers” refers tofibers which have been formed from at least two polymers extruded fromthe same extruder as a blend or mixture. Multiconstituent fibers do nothave the various polymer components arranged in relatively constantlypositioned distinct zones across the cross-sectional area of the fiberand the various polymers are usually not continuous along the entirelength of the fiber, instead usually forming fibrils or protofibrilswhich start and end at random.

[0040] As used herein, the phrase “fine meltblown filaments” is intendedto represent meltblown filaments having an average fiber diameter lessthan about 15 microns.

[0041] As used herein, the phrase “coarse meltblown filaments” isintended to represent meltblown filaments having an average fiberdiameter greater than about 15 microns.

[0042] As used herein, the phrase “dual texture” is intended to meanthat the nonwoven web has at least two distinct surface textures. Thetwo distinct surface textures may be on one or both sides of thenonwoven web. Preferably, there is a distinct surface texture on eachside of the nonwoven web.

[0043] As used herein, the term “abrasive” is intended to represent asurface texture which enables the nonwoven web to scour a surface beingwiped or cleaned with the nonwoven web and remove dirt and the like. Theabrasiveness can vary depending on the polymer used to prepare theabrasive fibers and the degree of texture of the nonwoven web.

[0044] As used herein, the term “non-abrasive” is intended to representa surface texture which relatively soft and generally does not have theability to scour a surface being wiped or cleaned with the nonwoven web.

DETAILED DESCRIPTION

[0045] The present invention provides a dual texture coform nonwoven webhaving a matrix containing 1) thermoplastic meltblown filaments and 2)at least one secondary material. The dual texture coform nonwoven webhas a first exterior surface and a second exterior surface, wherein thefirst exterior surface contains fine thermoplastic meltblown filamentshaving an average fiber diameter of less than about 15 microns and thesecondary material; and the second exterior surface contains coarsethermoplastic meltblown filaments having an average diameter in greaterthan about 15 microns and the secondary material.

[0046] The first and second surfaces of the dual texture nonwoven webcan contain both the coarse thermoplastic filaments and the finethermoplastic filaments. In the present invention, the coarsethermoplastic filaments can be incorporated into the dual texturenonwoven web matrix in a random manner, in a substantially homogenousmanner or in a gradient manner. Likewise the fine thermoplasticfilaments can be incorporated into the dual texture nonwoven web matrixin a random manner, in a substantially homogenous manner, or in agradient manner. It is preferred, but not required, that theconcentration of the coarse meltblown filaments in the matrix can be ina gradient type structure, decreasing in a direction from the secondexterior surface towards the first exterior surface. In addition, thecoform nonwoven web of the present invention can be a single layerstructure or a multi-layer structure. It is not critical to the presentinvention if the nonwoven web is a single layer or a multi-layerstructure.

[0047] The meltblown filaments, both the fine filaments and the coarsefilaments, are preferably prepared from thermoplastic polymers. Suitablethermoplastic polymers useful in the present invention includepolyolefins, polyesters, polyamides, polycarbonates, polyurethanes,polyvinylchloride, polytetrafluoroethylene, polystyrene, polyethyleneterephathalate, biodegradable polymers such as polylactic acid andcopolymers and blends thereof. Suitable polyolefins includepolyethylene, e.g., high density polyethylene, medium densitypolyethylene, low density polyethylene and linear low densitypolyethylene; polypropylene, e.g., isotactic polypropylene, syndiotacticpolypropylene, blends of isotactic polypropylene and atacticpolypropylene, and blends thereof; polybutylene, e.g., poly(1-butene)and poly(2-butene); polypentene, e.g., poly(1-pentene) andpoly(2-pentene); poly(3-methyl-1-pentene); poly(4-methyl 1-pentene); andcopolymers and blends thereof. Suitable copolymers include random andblock copolymers prepared from two or more different unsaturated olefinmonomers, such as ethylene/propylene and ethylene/butylene copolymers.Suitable polyamides include nylon 6, nylon 6/6, nylon 4/6, nylon 11,nylon 12, nylon 6/10, nylon 6/12, nylon 12/12, copolymers of caprolactamand alkylene oxide diamine, and the like, as well as blends andcopolymers thereof. Suitable polyesters include polyethyleneterephthalate, polytrimethylene terephthalate, polybutyleneterephthalate, polytetramethylene terephthalate,polycyclohexylene-1,4-dimethylene terephthalate, and isophthalatecopolymers thereof, as well as blends thereof.

[0048] Many polyolefins are available for fiber production, for examplepolyethylenes such as Dow Chemical's ASPUN 6811A linear low-densitypolyethylene, 2553 LLDPE and 25355 and 12350 high density polyethyleneare such suitable polymers. The polyethylenes have melt flow rates ing/10 min. at 190° F. and a load of 2.16 kg, of about 26, 40, 25 and 12,respectively. Fiber forming polypropylenes include, for example,Basell's PF-015 polypropylene. Many other polyolefins are commerciallyavailable and generally can be used in the present invention. Theparticularly preferred polyolefins are polypropylene and polyethylene.

[0049] Examples of polyamides and their methods of synthesis may befound in “Polymer Resins” by Don E. Floyd (Library of Congress Catalognumber 66-20811, Reinhold Publishing, N.Y., 1966). Particularlycommercially useful polyamides are nylon 6, nylon-6,6, nylon-11 andnylon-12. These polyamides are available from a number of sources suchas Custom Resins, Nyltech, among others. In addition, a compatibletackifying resin may be added to the extrudable compositions describedabove to provide tackified materials that autogenously bond or whichrequire heat for bonding. Any tackifier resin can be used which iscompatible with the polymers and can withstand the high processing(e.g., extrusion) temperatures. If the polymer is blended withprocessing aids such as, for example, polyolefins or extending oils, thetackifier resin should also be compatible with those processing aids.Generally, hydrogenated hydrocarbon resins are preferred tackifyingresins, because of their better temperature stability. REGALREZ® andARKON® P series tackifiers are examples of hydrogenated hydrocarbonresins. ZONATAC® 501 Lite is an example of a terpene hydrocarbon.REGALREZ® hydrocarbon resins are available from Hercules Incorporated.ARKON®P series resins are available from Arakawa Chemical (USA)Incorporated. The tackifying resins such as disclosed in U.S. Pat. No.4,787,699, hereby incorporated by reference, are suitable. Othertackifying resins which are compatible with the other components of thecomposition and can withstand the high processing temperatures, can alsobe used.

[0050] The meltblown filaments may be monocomponent fibers, meaningfibers prepared from one polymer component, multiconstituent fibers, ormulticomponent fibers. The multicomponent filaments may have either ofan A/B or A/B/A side-by-side configuration, or a sheath-coreconfiguration, wherein one polymer component surrounds another polymercomponent.

[0051] The secondary material of a coform nonwoven web of the presentinvention may be an absorbent material, such as absorbent fibers orabsorbent particles, or non-absorbent materials, such as non-absorbentfibers or non-absorbent particles. The selection of the second materialwill determine the properties of the resulting dual texture coformnonwoven web. For example, the absorbency of the coform nonwoven web canbe improved by using an absorbent material as the second material. Thecoform nonwoven web generally contains from about 5% to about 95% byweight of the absorbent material and about 95% to about 5% by weight ofthe thermoplastic meltblown filaments. Generally, the amount of thesecond material can be selected by those skilled in the art depending onthe final utility of the coform nonwoven web. The second material maymake up from about 20% to about 85% by weight of the coform nonwoven webor desirably about 30% to about 70% by weight of coform web.Correspondingly, the thermoplastic meltblown filaments make up about 15%to about 80% by weight of the coform nonwoven web or desirably about 30%to about 70% by weight of the coform nonwoven web. It is noted that theabove percentages for the meltblown filaments includes both the finemeltblown filaments and the coarse meltblown filaments.

[0052] The absorbent materials useful in the present invention includeabsorbent fibers, absorbent particles and mixtures of absorbent fibersand absorbent particles. Examples of the absorbent material include, butare not limited to, fibrous organic materials such as woody or non-woodypulp from cotton, rayon, recycled paper, pulp fluff and alsosuperabsorbent particles, inorganic absorbent materials, treatedpolymeric staple fibers and so forth. Desirably, although not required,the absorbent material is pulp, and/or superabsorbent fibers and/orparticles.

[0053] The pulp fibers may be any high-average fiber length pulp,low-average fiber length pulp, or mixtures of the same. Preferred pulpfibers include cellulose fibers. The term “high average fiber lengthpulp” refers to pulp that contains a relatively small amount of shortfibers and non-fiber particles. High fiber length pulps typically havean average fiber length greater than about 1.5 mm, preferably about1.5-6 mm. Sources generally include non-secondary (virgin) fibers aswell as secondary fiber pulp which has been screened. The term “lowaverage fiber length pulp” refers to pulp that contains a significantamount of short fibers and non-fiber particles. Low average fiber lengthpulps typically have an average fiber length less than about 1.5 mm.

[0054] Examples of high average fiber length wood pulps include thoseavailable from Georgia-Pacific under the trade designations Golden Isles4821 and 4824. The low average fiber length pulps may include certainvirgin hardwood pulp and secondary (i.e., recycled) fiber pulp fromsources including newsprint, reclaimed paperboard, and office waste.Mixtures of high average fiber length and low average fiber length pulpsmay contain a predominance of low average fiber length pulps. Forexample, mixtures may contain more than about 50% by weight low-averagefiber length pulp and less than about 50% by weight high-average fiberlength pulp. One exemplary mixture contains about 75% by weightlow-average fiber length pulp and about 25% by weight high-average fiberlength pulp.

[0055] The pulp fibers may be unrefined or may be beaten to variousdegrees of refinement. Crosslinking agents and/or hydrating agents mayalso be added to the pulp mixture. Debonding agents may be added toreduce the degree of hydrogen bonding if a very open or loose nonwovenpulp fiber web is desired. Exemplary debonding agents are available fromthe Quaker Oats Chemical Company, Conshohocken, Pa., under the tradedesignation Quaker 2028 and Berocell 509ha made by Eka Nobel, Inc.Marietta, Ga. The addition of certain debonding agents in the amount of,for example, 1-4% by weight of the pulp fibers, may reduce the measuredstatic and dynamic coefficients of friction and improve the abrasionresistance of the thermoplastic meltblown polymer filaments. Thedebonding agents act as lubricants or friction reducers. Debonded pulpfibers are commercially available from Weyerhaeuser Corp. under thedesignation NB 405.

[0056] In another highly advantageous embodiment, a quantity of asuperabsorbent material is combined with the thermoplastic meltblownpolymer filaments, to improve the absorbency of the absorbent nonwovenweb, with or without pulp fibers. The term “superabsorbent” or“superabsorbent material” refers to a water-swellable, water-insolubleorganic or inorganic material capable, under the most favorableconditions, of absorbing at least about 10 times its weight and, moredesirably, at least about 30 times its weight in an aqueous solutioncontaining 0.9 weight percent sodium chloride, at room temperature andpressure.

[0057] The superabsorbent materials can be natural, synthetic andmodified natural polymers and materials. In addition, the superabsorbentmaterials can be inorganic materials, such as silica gels, or organiccompounds such as cross-linked polymers. The term “cross-linked” refersto any means for effectively rendering normally water-soluble materialssubstantially water insoluble but swellable. Such means can include, forexample, physical entanglement, crystalline domains, covalent bonds,ionic complexes and associations, hydrophilic associations, such ashydrogen bonding, and hydrophobic associations or Van der Waals forces.

[0058] Examples of synthetic superabsorbent material polymers includethe alkali metal and ammonium salts of poly(acrylic acid) andpoly(methacrylic acid), poly(acrylamides), poly(vinyl ethers), maleicanhydride copolymers with vinyl ethers and alpha-olefins, poly(vinylpyrrolidone), poly(vinylmorpholinone), poly(vinyl alcohol), and mixturesand copolymers thereof. Further superabsorbent materials include naturaland modified natural polymers, such as hydrolyzed acrylonitrile-graftedstarch, acrylic acid grafted starch, methyl cellulose, chitosan,carboxymethyl cellulose, hydroxypropyl cellulose, and the natural gums,such as alginates, xanthan gum, locust bean gum and the like. Mixturesof natural and wholly or partially synthetic superabsorbent polymers canalso be useful in the present invention. Other suitable absorbentgelling materials are disclosed by Assarsson et al. in U.S. Pat. No.3,901,236 issued Aug. 26, 1975. Processes for preparing syntheticabsorbent gelling polymers are disclosed in U.S. Pat. No. 4,076,633issued Feb. 28, 1978 to Masuda et al. and U.S. Pat. No. 4,286,082 issuedAug. 25, 1981 to Tsubakimoto et al, each hereby incorporated byreference.

[0059] Superabsorbent materials may be xerogels which form hydrogelswhen wetted. The term “hydrogel,” however, has commonly been used toalso refer to both the wetted and unwetted forms of the superabsorbentpolymer material. The superabsorbent materials can be in many forms suchas flakes, powders, particulates, fibers, continuous fibers, networks,solution spun filaments and webs. The particles can be of any desiredshape, for example, spiral or semi-spiral, cubic, rod-like, polyhedral,etc. Needles, flakes, fibers, and combinations may also be used.

[0060] Superabsorbents are generally available in particle sizes rangingfrom about 20 to about 1000 microns. Examples of commercially availableparticulate superabsorbents include SANWET® IM 3900 and SANWET®IM-5000P, available from Hoescht Celanese located in Portsmouth, Va.,SANWET® 2035LD available from Dow Chemical Co. located in Midland,Mich., and FAVOR® 880, available from Stockhausen, located inGreensborough, N.C. An example of a fibrous superabsorbent is OASIS®101, available from Technical Absorbents, located in Grimsby, UnitedKingdom.

[0061] When used, the superabsorbent material may be present within theabsorbent nonwoven web in an amount from about 5 to about 75% by weightbased on total weight of the coform nonwoven web. Preferably, thesuperabsorbent constitutes about 10-60% by weight of the coform nonwovenweb, more preferably about 20-50% by weight. When the superabsorbentmaterial is present, other absorbent fibers or particles may or may notbe present. It is preferred, however, that the total weight of theabsorbent material, including both the superabsorbent material and theother absorbent material, such as pulp, in the absorbent nonwoven web isbetween about 5 and about 95% by weight of the nonwoven web.

[0062] When the absorbent material contains a mixture of asuperabsorbent material and a non-superabsorbent material, such as pulp,the superabsorbent desirably is present in an amount less than about 50%by weight of the absorbent material present in the absorbent nonwovenweb. This is because superabsorbent materials are generally slow toabsorb fluids and/or release fluids. More preferably, the superabsorbentmaterial is present in an amount of about 5 to about 25% by weight ofthe absorbent material present in dual texture coform nonwoven web. Ineach case, the balance of the absorbent material is a non-superabsorbentmaterial, such as pulp.

[0063] In addition, non-absorbent secondary materials can beincorporated into the dual texture coform nonwoven web, depending on theend use of the dual texture coform nonwoven web. For example, in enduses where absorbency is not an issue, non-absorbent secondary materialsmay be used. These non-absorbent materials include nonabsorbent fibersand nonabsorbent particles. Examples of the fibers include, for example,staple fibers of untreated thermoplastic polymers, such as polyolefinsand the like. Examples of nonabsorbent particles include activatedcharcoal, sodium bicarbonate and the like. The nonabsorbent material canbe used alone or in combination with the absorbent material. It shouldbe noted, however, that the total amount of the second material, whetherabsorbent or nonabsorbent should be between 5 and 95% by weight of thetotal weight of the dual texture coform nonwoven web, more preferablybetween about 30% and 70% by weight.

[0064] The secondary material may be incorporated into the dual texturenonwoven web in a gradient manner such that the concentration of thesecondary material is lower at the surfaces and higher in the centerportion of the nonwoven web, in a random manner or substantiallyhomogenous distributed though-out the nonwoven web. Preferably, thesecondary material is substantially homogenously distributed throughoutthe nonwoven web, wherein the exterior surfaces of the nonwoven webcontain some of the secondary material.

[0065] The dual texture coform nonwoven web of the present invention isprepared by a method including:

[0066] a. providing a first stream of meltblown filaments having anaverage diameter of less than about 15 microns;

[0067] b. providing a second stream of meltblown filaments having anaverage diameter greater than about 15 microns:

[0068] c. converging the first stream of meltblown filaments and thesecond stream of meltblown filaments in an intersecting relationship toform an impingement zone;

[0069] d. introducing a stream containing at least one secondarymaterial between the first and second streams of the meltblown filamentsat or near the impingement zone to form a composite stream; and

[0070] e. depositing the composite stream onto a forming surface as amatrix of meltblown filaments and at least one secondary material toform a nonwoven web containing a first and a second exterior surface;the first exterior surface contains fine meltblown fibers having averagediameter of less than about 15 microns and the secondary material, andthe second exterior surface contains coarse meltblown fibers having anaverage diameter greater than about 15 microns and the secondarymaterial. In order to obtain a better understanding of how to producethe dual texture coform nonwoven web of the present invention, attentionis directed to FIG. 1. FIG. 1 shows an exemplary apparatus for forming adual texture coform nonwoven web which is generally represented byreference numeral 10. In forming the dual texture coform nonwoven web ofthe present invention, pellets or chips, etc. (not shown) of athermoplastic polymer are introduced into a pellet hopper 12, or 12′ ofan extruder 14 or 14′, respectively.

[0071] The extruders 14 and 14′ each have an extrusion screw (notshown), which is driven by a conventional drive motor (not shown). Asthe polymer advances through the extruders 14 and 14′, due to rotationof the extrusion screw by the drive motor, it is progressively heated toa molten state. Heating the thermoplastic polymer to the molten statemay be accomplished in a plurality of discrete steps with itstemperature being gradually elevated as it advances through discreteheating zones of the extruders 14 and 14′ toward two meltblowing dies 16and 18, respectively. The meltblowing dies 16 and 18 may be yet anotherheating zone where the temperature of the thermoplastic resin ismaintained at an elevated level for extrusion.

[0072] Each meltblowing die is configured so that two streams ofattenuating gas per die converge to form a single stream of gas whichentrains and attenuates molten threads 20 and 21, as the threads 20 and21 exit small holes or orifices 24 and 24′, respectively in eachmeltblowing die. The molten threads 20 and 21 are formed into fibers or,depending upon the degree of attenuation, microfibers, of a smalldiameter which is usually less than the diameter of the orifices 24.Thus, each meltblowing die 16 and 18 has a corresponding single streamof gas 26 and 28 containing entrained thermoplastic polymer fibers. Thegas streams 26 and 28 containing polymer fibers are aligned to convergeat an impingement zone 30.

[0073] One or more types of secondary fibers 32 and/or particulates areadded to the two streams 26 and 28 of thermoplastic polymer fibers 20and 21, respectively, and at the impingement zone 30. Introduction ofthe secondary fibers 32 into the two streams 26 and 28 of thermoplasticpolymer fibers 20 and 21, respectively, is designed to produce agraduated distribution of secondary fibers 32 within the combinedstreams 26 and 28 of thermoplastic polymer fibers. This may beaccomplished by merging a secondary gas stream 34 containing thesecondary fibers 32 between the two streams 26 and 28 of thermoplasticpolymer fibers 20 and 21 so that all three gas streams converge in acontrolled manner.

[0074] Apparatus for accomplishing this merger may include aconventional picker roll 36 arrangement which has a plurality of teeth38 that are adapted to separate a mat or batt 40 of secondary fibersinto the individual secondary fibers 32. The mat or batt of secondaryfibers 40 which is fed to the picker roll 36 may be a sheet of pulpfibers (if a two-component mixture of thermoplastic polymer fibers andsecondary pulp fibers is desired), a mat of staple fibers (if atwo-component mixture of thermoplastic polymer fibers and a secondarystaple fibers is desired) or both a sheet of pulp fibers and a mat ofstaple fibers (if a three-component mixture of thermoplastic polymerfibers, secondary staple fibers and secondary pulp fibers is desired).In embodiments where, for example, an absorbent material is desired, thesecondary fibers 32 are absorbent fibers. The secondary fibers 32 maygenerally be selected from the group including one or more polyesterfibers, polyamide fibers, cellulosic derived fibers such as, forexample, rayon fibers and wood pulp fibers, multi-component fibers suchas, for example, sheath-core multi-component fibers, natural fibers suchas silk fibers, wool fibers or cotton fibers or electrically conductivefibers or blends of two or more of such secondary fibers. Other types ofsecondary fibers 32 such as, for example, polyethylene fibers andpolypropylene fibers, as well as blends of two or more of other types ofsecondary fibers 32 may be utilized. The secondary fibers 32 may bemicrofibers or the secondary fibers 32 may be macrofibers having anaverage diameter of from about 300 microns to about 1,000 microns.

[0075] The sheets or mats 40 of secondary fibers 32 are fed to thepicker roll 36 by a roller arrangement 42. After the teeth 38 of thepicker roll 36 have separated the mat of secondary fibers 40 intoseparate secondary fibers 32 the individual secondary fibers 32 areconveyed toward the stream of thermoplastic polymer fibers ormicrofibers 24 through a nozzle 44. A housing 46 encloses the pickerroll 36 and provides a passageway or gap 48 between the housing 46 andthe surface of the teeth 38 of the picker roll 36. A gas, for example,air, is supplied to the passageway or gap 46 between the surface of thepicker roll 36 and the housing 48 by way of a gas duct 50.

[0076] The gas duct 50 may enter the passageway or gap 46 generally atthe junction 52 of the nozzle 44 and the gap 48. The gas is supplied insufficient quantity to serve as a medium for conveying the secondaryfibers 32 through the nozzle 44. The gas supplied from the duct 50 alsoserves as an aid in removing the secondary fibers 32 from the teeth 38of the picker roll 36. The gas may be supplied by any conventionalarrangement such as, for example, an air blower (not shown). It iscontemplated that additives and/or other materials may be added to orentrained in the gas stream to treat the secondary fibers.

[0077] Generally speaking, the individual secondary fibers 32 areconveyed through the nozzle 44 at about the velocity at which thesecondary fibers 32 leave the teeth 38 of the picker roll 36. In otherwords, the secondary fibers 32, upon leaving the teeth 38 of the pickerroll 36 and entering the nozzle 44 generally maintain their velocity inboth magnitude and direction from the point where they left the teeth 38of the picker roll 36.

[0078] Such an arrangement, which is discussed in more detail in U.S.Pat. No. 4,100,324 to Anderson, et al., hereby incorporated byreference, aids in substantially reducing fiber floccing.

[0079] The width of the nozzle 44 should be aligned in a directiongenerally parallel to the width of the meltblowing dies 16 and 18.Desirably, the width of the nozzle 44 should be about the same as thewidth of the meltblowing dies 16 and 18. Usually, the width of thenozzle 44 should not exceed the width of the sheets or mats 40 that arebeing fed to the picker roll 36. Generally speaking, it is desirable forthe length of the nozzle 44 to be as short as equipment design willallow.

[0080] The picker roll 36 may be replaced by a conventional particulateinjection system to form a coform nonwoven structure 54 containingvarious secondary particulates. A combination of both secondaryparticulates and secondary fibers could be added to the thermoplasticpolymer fibers prior to formation of the coform nonwoven structure 54 ifa conventional particulate injection system was added to the systemillustrated in FIG. 1. The particulates may be, for example, charcoal,clay, starches, and/or superabsorbent particles.

[0081]FIG. 1 further illustrates that the secondary gas stream 34carrying the secondary fibers 32 is directed between the streams 26 and28 of thermoplastic polymer fibers so that the streams contact at theimpingement zone 30. The velocity of the secondary gas stream 34 may beadjusted. If the velocity of the secondary gas stream is adjusted sothat it is greater than the velocity of each stream 26 and 28 ofthermoplastic polymer fibers 20 and 21 when the streams contact at theimpingement zone 30, the secondary material is incorporated in thecoform nonwoven web in a gradient structure. That is, the secondarymaterial has a higher concentration between the outer surfaces of thecoform nonwoven web than at the outer surfaces. If the velocity of thesecondary gas stream 34 is less than the velocity of each stream 26 and28 of thermoplastic polymer fibers 20 and 21 when the streams contact atthe impingement zone 30, the secondary material is incorporated in thecoform nonwoven web in a substantially homogenous fashion. That is, theconcentration of the secondary material is substantially the samethroughout the coform nonwoven web. This is because the low-speed streamof secondary material is drawn into a high-speed stream of thermoplasticpolymer fibers to enhance turbulent mixing which results in a consistentdistribution of the secondary material.

[0082] Although the inventors should not be held to a particular theoryof operation, it is believed that adjusting the velocity of thesecondary gas stream 34 so that it is greater than the velocity of eachstream 26 and 28 of thermoplastic polymer fibers 24 when the streamsintersect at the impingement zone 30 can have the effect that, duringmerger and integration thereof, between the impingement zone 30 and acollection surface, a graduated distribution of the fibrous componentscan be accomplished.

[0083] The velocity difference between the gas streams may be such thatthe secondary fibers 32 are integrated into the streams of thermoplasticpolymer fibers 26 and 28 in such manner that the secondary material 32become gradually and only partially distributed within the thermoplasticpolymer fibers 20 and 21. Generally, for increased production rates thegas streams which entrain the thermoplastic polymer fibers 20 and 21 mayhave a comparatively high initial velocity, for example, from about 200feet to over 1,000 feet per second. However, the velocity of those gasstreams decreases rapidly as they expand and become separated from themeltblowing die. Thus, the velocity of those gas streams at theimpingement zone may be controlled by adjusting the distance between themeltblowing die and the impingement zone. The stream of gas 34 whichcarries the secondary fibers 32 will have a low initial velocity whencompared to the gas streams 26 and 28 which carry the meltblown fibers.However, by adjusting the distance from the nozzle 44 to the impingementzone 30 (and the distances that the meltblown fiber gas streams 26 and28 must travel), the velocity of the gas stream 34 can be controlled tobe greater or lower than the meltblown fiber gas streams 26 and 28. Inthe practice of the present invention, it is preferred that the pulp ishomogenously integrated with both the coarse and fine meltblownfilaments. In addition, the velocity of the thermoplastic fiber streamsmay also be adjusted to obtain the desired degree of mixing.

[0084] Due to the fact that the thermoplastic polymer fibers 20 and 21are usually still semi-molten and tacky at the time of incorporation ofthe secondary fibers 32 into the thermoplastic polymer fiber streams 26and 28, the secondary fibers 32 are usually not only mechanicallyentangled within the matrix formed by the thermoplastic polymer fibers20 and 21 but are also thermally bonded or joined to the thermoplasticpolymer fibers 20 and 21.

[0085] In order to convert the composite stream 56 of thermoplasticpolymer fibers 20, 21 and secondary material 32 into a coform nonwovenstructure 54, a collecting device is located in the path of thecomposite stream 56. The collecting device may be an endless belt 58conventionally driven by rollers 60 and which is rotating as indicatedby the arrow 62 in FIG. 1. Other collecting devices are well known tothose of skill in the art and may be utilized in place of the endlessbelt 58. For example, a porous rotating drum arrangement could beutilized. The merged streams of thermoplastic polymer fibers andsecondary fibers are collected as a coherent matrix of fibers on thesurface of the endless belt 58 to form the coform nonwoven web 54.Vacuum boxes 64 assist in retention of the matrix on the surface of thebelt 58.

[0086] The coform structure 54 is coherent and may be removed from thebelt 58 as a self-supporting nonwoven material. Generally speaking, thecoform structure has adequate strength and integrity to be used withoutany post-treatments such as pattern bonding and the like. If desired, apair of pinch rollers or pattern bonding rollers may be used to bondportions of the material. Although such treatment may improve theintegrity of the nonwoven web structure 54, it also tends to compressand densify the structure.

[0087] In the present invention, one meltblown stream 26 or 28 carriesthermoplastic filaments having coarse meltblown fibers, having anaverage fiber diameter greater than about 15 microns. The othermeltblown fiber stream carries thermoplastic filaments having an averagefiber diameter of less than about 15 microns. Depending on variousfactors, including but not limited to, the velocity of the meltblownstreams 26 and 26, the velocity of the secondary material stream 34, thecharacteristics of the resulting dual texture coform nonwoven web can bechanged. For example, all of the thermoplastic filaments and secondarymaterial can be substantially uniformly mixed, the absorbent materialcan be present in a gradient type structure, or absorbent material ispresent in a uniform type manner in the coform nonwoven web while thecoarse fiber meltblown is present in a gradient type manner. In usingthis process, it is desirable, although not required, that the twosurfaces of the coform nonwoven web have different characteristics. Onesurface will have an abrasive characteristic, which allows scrubbing ona surface to be cleaned and the other surface will have soft,nonabrasive feeling.

[0088] In addition, the concentration of the coarse meltblown fibers inthe coform nonwoven web decreases from the surface having the abrasivecharacteristic towards the surface having the non-abrasivecharacteristic. Likewise, the concentration of the fine meltblown fibersin the coform nonwoven web decreases from the surface having thenon-abrasive characteristic towards the surface having the abrasivecharacteristic. This can be seen in FIG. 4.

[0089] As an alternative method, the dual texture meltblown may beprepared by a method including the steps of:

[0090] a. providing a first stream of meltblown filaments;

[0091] b. introducing a stream containing at least one secondarymaterial to the first stream of meltblown filaments to form a firstcomposite stream;

[0092] c. providing a second stream of meltblown filaments;

[0093] d. introducing a stream at least one secondary material to thesecond stream of meltblown filaments to form a second composite stream;

[0094] e. depositing the first composite stream onto a forming surfaceas a matrix of meltblown filaments and a secondary material to form afirst deposited layer; and

[0095] f. depositing the second composite stream onto the firstdeposited layer as a matrix of meltblown filaments and a secondarymaterial to form a coform nonwoven web;

[0096] wherein one of the first stream of meltblown filaments or thesecond stream of meltblown filaments contains meltblown filaments havingaverage diameter of less than about 15 microns and the other of thefirst stream of meltblown fibers or the second stream of meltblownfibers contains meltblown filaments having an average diameter greaterthan about 15 microns. This method sequentially lays down a coarsemeltblown filament/secondary material layer and a fine meltblownfilament/secondary material layer. It is noted that it is not criticalto the present invention whether the first or second stream of meltblownfilaments is the stream with the coarse meltblown filaments.

[0097] In this regard, attention is directed to FIG. 2, which shows anexemplary apparatus for forming a dual texture coform nonwoven web whichis generally represented by reference numeral 100. In forming the dualtexture coform nonwoven web of the present invention, pellets or chips,etc. (not shown) of a thermoplastic polymer are introduced into a pellethopper 112, or 112′ of an extruder 114 or 114′, respectively.

[0098] The extruders 114 and 114′ each have an extrusion screw (notshown), which is driven by a conventional drive motor (not shown). Asthe polymer advances through the extruders 114 and 114′, due to rotationof the extrusion screw by the drive motor, it is progressively heated toa molten state. Heating the thermoplastic polymer to the molten statemay be accomplished in a plurality of discrete steps with itstemperature being gradually elevated as it advances through discreteheating zones of the extruders 114 and 114′ toward two meltblowing dies116 and 118, respectively. The meltblowing dies 116 and 118 may be yetanother heating zone where the temperature of the thermoplastic resin ismaintained at an elevated level for extrusion.

[0099] Each meltblowing die is configured so that two streams ofattenuating gas 117 and 117′ per die converge to form a single stream ofgas which entrains and attenuates molten threads 120 and 121, as thethreads 120 and 121 exit small holes or orifices 124 and 124′,respectively. The molten threads 120 and 121 are formed into filamentsor, depending upon the degree of attenuation, microfibers, of a smalldiameter which is usually less than the diameter of the orifices 124 and124′. Thus, each meltblowing die 116 and 118 has a corresponding singlestream of gas 126 and 128 containing entrained thermoplastic polymerfibers. The gas streams 126 and 128 containing polymer fibers directedtoward the forming surface and are generally preferred to besubstantially perpendicular to the forming surface.

[0100] One or more types of secondary fibers 132 and 132′ and/orparticulates are added to the two streams 126 and 128 of thermoplasticpolymer fibers 120 and 121, respectively. Introduction of the secondaryfibers 132 and 132′ into the two streams 126 and 128 of thermoplasticpolymer fibers 120 and 121, respectively, is designed to produce agenerally homogenous distribution of secondary fibers 132 and 132′within streams 126 and 128 of thermoplastic polymer fibers.

[0101] Apparatus for accomplishing this merger may include aconventional picker roll 136 and 136′. The operation of a conventionalpicker roll is described above for in the discussion of FIG. 1. Thepicker rolls 136 and 136′ may be replaced by a conventional particulateinjection system to form a coform nonwoven structure 154 containingvarious secondary particulates. A combination of both secondaryparticulates and secondary fibers could be added to the thermoplasticpolymer fibers prior to formation of the coform nonwoven structure 154if a conventional particulate injection system was added to the systemillustrated in FIG. 2. The particulates may be, for example, charcoal,clay, starches, and/or superabsorbent particles.

[0102] Due to the fact that the thermoplastic polymer fibers 120 and 121are usually still semi-molten and tacky at the time of incorporation ofthe secondary fibers 132 and 132′ into the thermoplastic polymer fiberstreams 126 and 128, the secondary fibers 132 and 132′ are usually notonly mechanically entangled within the matrix formed by thethermoplastic polymer fibers 120 or 121′ but are also thermally bondedor joined to the thermoplastic polymer fibers 120 or 121′.

[0103] In order to convert the composite stream 156 and 156′ ofthermoplastic polymer fibers 120, 121 and secondary material 132 and132′, respectively, into a coform nonwoven structure 154, a collectingdevice is located in the path of the composite streams 156 and 156′. Thecollecting device may be an endless belt 158 conventionally driven byrollers 160 and which is rotating as indicated by the arrow 162 in FIG.2. Other collecting devices are well known to those of skill in the artand may be utilized in place of the endless belt 158. For example, aporous rotating drum arrangement could be utilized. The merged streamsof thermoplastic polymer fibers and secondary fibers are collected as acoherent matrix of fibers on the surface of the endless belt 158 to formthe coform nonwoven web 154. Vacuum boxes 164 and 164′ assist inretention of the matrix on the surface of the belt 158.

[0104] The coform structure 154 is coherent and may be removed from thebelt 158 as a self-supporting nonwoven material. Generally speaking, thecoform structure has adequate strength and integrity to be used withoutany post-treatments such as pattern bonding, calendering and the like.However, the structure can be further stabilized by thermally bonding orcompressing the coform structure. For example, a pair of pinch rollersor pattern bonding rollers, which may or may not be heated, may be usedto bond portions of the material. Although such treatment may improvethe integrity of the coform nonwoven web structure 154, it also tends tocompress and densify the structure.

[0105] In the present invention, one meltblown stream 126 or 128 carriesthermoplastic filaments having coarse meltblown fibers, having anaverage fiber diameter greater than about 15 microns. The othermeltblown fiber stream carries thermoplastic filaments having an averagefiber diameter of less than about 15 microns. As a result, the twosurfaces of the coform nonwoven web have different characteristics. Onesurface will have an abrasive characteristic, which allows scrubbing ona surface to be cleaned and the other surface will have soft,nonabrasive feeling. Although it is not critical to the presentinvention which stream is used to produce the coarse meltblownfilaments, generally stream 128 is the stream used to produce the coarsemeltblown filaments.

[0106] The characteristics of the meltblown filaments can be adjusted bymanipulation of the various process parameters used for each extruderand die head in carrying out the meltblowing process. The followingparameters can be adjusted and varied for each extruder and die head inorder to change the characteristics of the resulting meltblownfilaments:

[0107] 1. Type of Polymer,

[0108] 2. Polymer throughput (pounds per inch of die width perhour—PIH),

[0109] 3. Polymer melt temperature,

[0110] 4. Air temperature,

[0111] 5. Air flow (standard cubic feet per minute, SCFM, calibrated thewidth of the die head),

[0112] 6. Distance from between die tip and forming belt and

[0113] 7. Vacuum under forming belt.

[0114] For example, the coarse filaments may be prepared by reducing theprimary air temperature from the range of about 5000-540° F. (260°-282°C.) to about 420°-460° F. (2160-2380° C.) for the coarse filament bank.These changes result in the formation of larger fibers. Any other methodwhich is effective may also be used and would be in keeping with theinvention.

[0115] In practice of the present invention, the average fiber diameterof the coarse meltblown filaments are preferably in the range of about15 to about 39 microns, more preferably in the range of about 20 toabout 35 microns. The average fiber diameter of the fine meltblownfilaments is preferably less than 12 microns, more preferably less than8 microns and most preferably about 0.5-5 microns.

[0116] Preparing the coform nonwoven web by the second method disclosedabove has some additional advantages over intermingling the finemeltblown filaments, coarse meltblown filaments and pulp. Specifically,the amount of second material can be varied at each surface of thecoform nonwoven web, giving a coform nonwoven web with a layeredstructure. Each layer of the layered structure may have the same ordifferent percentages of the secondary material and/or may contain thesame or different secondary materials. One advantage of being able tomodify the secondary material content is that the coarse filamentssometimes do not capture the secondary material as well as the finefiber, especially at high secondary material content, which may causelinting of secondary material from the coform nonwoven web. Generally,it is preferred, but not required, that the secondary material contentin the coarse meltblown containing surface is about 20% to about 80% byweight of the coarse meltblown and secondary material mixture. A morepreferred range is about 30% to about 65% by weight of the secondarymaterial in the coarse meltblown filament containing surface. Inaddition, varying the amount of the secondary material at each surfacecan help the fluid distribution within the coform nonwoven web bycreating a gradient structure for the secondary material. Further, it ispreferred, but not required, that the secondary material content in thefine meltblown containing surface is about 20% to about 85% by weight ofthe fine meltblown and secondary material mixture. A more preferredrange is about 30% to about 70% by weight of the secondary material inthe fine meltblown filament containing surface. However, if thesecondary material content is greater than about 65-70% by weight in alayer, it is preferred that an additional layer be placed onto thecoform material to help prevent the secondary material from “linting”out of the coform. Additional layers are discussed below.

[0117] The coform material preferably has a total basis weight in therange of about 34 gsm to about 600 gsm. More preferably, the basisweight is in the range of about 75 gsm to about 400 gsm. Mostpreferably, the basis weight should be in the range of about 100 gsm toabout 325 gsm. It is pointed out, however, that the basis weight ishighly dependent on the end use. For pre-saturated mop applications itis preferred that the basis weight is about 75 gsm to about 325 gsm,while the basis weight for a absorbent mop is preferably in the range ofabout 175 gsm to about 325 gsm. For hand wipes and the like, the basisweight is generally dependent of the particular utility of the wipe. Inthe production of the dual texture coform by the apparatus of FIG. 2,the percentage of the basis weight can be varied. Generally, the finefiber coform layer can constitute between about 35 and about 65% byweight of the overall laminate. Likewise, the coarse fiber coform layercan constitute between about 35% and about 65% by weight of the overalllaminate. More preferably, the fine fiber coform layer is about 40% toabout 60% by weight of the overall coform material, and ideally about50% by weight.

[0118] The coform material of the present invention can be prepared onor laminated to an additional material. It is pointed out that thislamination is not required in the present invention. For example, anadditional material may be supplied to the process of FIG. 1 or FIG. 2before or after the formation of the coform material. If the material issupplied before the formation of the coform, the coform is formed on theadditional material. That is, the additional layer is laid down on theforming surface and the coform is placed on the additional layer. In thealternative, the additional layer may be laminated to the coform of thepresent invention after the coform is formed. If an additional layer islaminated to the coform material, or if the coform material is preparedon an additional material, it is preferred that the surface of thecoform nonwoven web which has the fine filaments is in contact with thematerial which is laminated to the coform material. This will stillprovide a coform material with an abrasive surface which can be used forscrubbing. As is noted above, lamination of an additional material tothe coform is not required, however, if the secondary material contentis greater than about 65-70% by weight in the coform material, it ispreferred that an additional layer be placed onto the coform material tohelp prevent the secondary material from “linting” out of the coform.

[0119] The additional layer can provide additional strength to thecoform or provides other properties, such as barrier properties.Laminating another material to the fine filament side of the coform isespecially useful in mop applications, by providing extra strength tothe nonwoven web and by providing a liquid barrier between the mopmaterial and the mop attachment means. Examples of barrier materialsinclude, for example such as polymeric films, laminate nonwovenmaterials, combinations thereof and the like. Generally, any materialwhich is liquid impervious may be any suitable. Examples ofstrengthening layers include, nonwoven webs, such as spunbond, bondedcarded webs and the liked, knitted webs, and woven materials. Thesematerials are known to those skilled in the art and are readilyavailable.

[0120] Due to cost considerations, spunbond materials are preferablylaminated to the fine filament side of the nonwoven web in order toprovide additional strength to the coform material, if a material is tobe laminated to the coform nonwoven web of the present invention.Typically, a spunbond having a basis weight in the range of 0.1 gsm toabout 2.0 gsm, more preferably about 0.2 gsm to about 0.8 gsm, ispreferred.

[0121] In another alternative laminate structure of the presentinvention, the coform nonwoven web may also have a barrier layer. Theliquid barrier layer desirably comprises a material that substantiallyprevents the transmission of liquids under the pressures and chemicalenvironments associated with surface cleaning applications. Desirably,the liquid barrier layer comprises a thin, monolithic film. The filmdesirably comprises a thermoplastic polymer such as, for example,polyolefins (e.g., polypropylene and polyethylene), polycondensates(e.g., polyamides, polyesters, polycarbonates, and polyarylates),polyols, polydienes, polyurethanes, polyethers, polyacrylates,polyacetals, polyimides, cellulose esters, polystyrenes, fluoropolymersand so forth. Desirably, the film is hydrophobic. Additionally, the filmdesirably has a thickness less than about 2 mil and still more desirablybetween about 0.5 mil and about 1 mil. As a particular example, theliquid barrier layer can comprise an embossed, polyethylene film havinga thickness of approximately 1 mil.

[0122] The liquid barrier layer can be bonded together with the otherlayer or layers of the cleaning sheet to form an integrated laminatethrough the use of adhesives. In a further aspect, the layers can beattached by mechanical means such as, for example, by stitching. Stillfurther, the multiple layers can be thermally and/or ultrasonicallylaminated together to form an integrated laminate. The method of bondingis not critical to the present invention.

[0123] The dual texture coform nonwoven web of the present invention canbe used to form a pre-saturated or absorbent cleaning sheet, used as awiper, a sheet for a mop or other hand held implements. The term“cleaning sheet” encompasses dry wipes, pre-saturated wipes, absorbentmops, pre-saturated mops and the like. The size and shape of thecleaning sheet can vary with respect to the intended application and/orend use of the same. Desirably, the cleaning has a substantiallyrectangular shape of a size which allows it to readily engage standardcleaning equipment or tools such as, for example, mop heads, dusterheads, brush heads and so forth. For example, the cleaning sheet mayhave an unfolded length of from about 2.0 to about 80.0 centimeters anddesirably from about 10.0 to about 25.0 centimeters and an unfoldedwidth of from about 2.0 to about 80.0 centimeters and desirably fromabout 10.0 to about 25.0 centimeters. As one particular example, inorder to fit a standard mop head, the cleaning sheet may have a lengthof about 28 cm and a width of about 22 cm. However, the particular sizeand/or shape of cleaning sheet can vary as needed to fit upon orotherwise conform to a specific cleaning tool. In an alternativeconfiguration, the cleaning sheet of the present invention could beformed into a mitten shaped article for wiping and cleaning, which wouldfit over the user's hand.

[0124] As indicated herein above, the cleaning sheets of the presentinvention are well suited for use with a variety of cleaning equipmentand, more particularly, are readily capable of being releasably-attachedto the head of a cleaning tool. As used herein, “releasably-attached” or“releasably-engaged” means that the sheet can be readily affixed to andthereafter readily removed from the cleaning tool. In reference to FIG.3, cleaning tool 240 can comprise handle 248, head 244 and fasteners246. Cleaning sheet 243 can be superposed with and placed against head244 such that the liquid barrier layer, if present, faces head 244. Ifthe cleaning sheet is a multilayer laminate, the side of the sheet withthe abrasive surface should face away from the head. Flaps 247 can thenbe wrapped around head 244 and releasably-attached to head 244 byfasteners 246, e.g. clamps. With cleaning sheet 243 affixed to head 244,cleaning tool 240 can then be used in one or more wet and/or drycleaning operations. Thereafter, when the cleaning sheet becomes heavilysoiled or otherwise spent, the used sheet can be quickly and easilyremoved and a new one put in its place. The specific configuration ofthe cleaning tool can vary in many respects. As examples, the sizeand/or shape of the handle can vary, the head can be fixed or moveable(e.g. pivotable) with relation to the handle, the shape and/or size ofthe head can vary, etc. Further, the composition of the head can itselfvary, as but one example the head can comprise a rigid structure with orwithout additional padding. Further, the mechanism(s) for attaching thecleaning sheet can vary and exemplary means of attachment include, butare not limited to, hook and loop type fasteners (e.g. VELCRO™fasteners), clamps, snaps, buttons, flaps, cinches, low tack adhesivesand so forth.

[0125] The cleaning sheets of the present invention are well suited fora variety of dry and wet cleaning operations such as: mopping floors;cleaning of dry surfaces: cleaning and drying wet surfaces such ascounters, tabletops or floors (e.g. wet surfaces resulting from spills);sterilizing and/or disinfecting surfaces by applying liquiddisinfectants; wiping down and/or cleaning appliances, machinery orequipment with liquid cleansers; rinsing surfaces or articles with wateror other diluents (e.g. to remove cleaners, oils, etc.), removing dirt,dust and/or other debris and so forth. The cleaning sheets have numeroususes as a result of its combination of physical attributes, especiallythe uptake and retention dirt, dust and/or debris. Additionally, thecleaning sheet provides a durable cleaning surface with good abrasionresistance. This combination of physical attributes is highlyadvantageous for cleaning surfaces with or without liquids such as soapand water or other common household cleaners. Further, the cleaningfabrics of the present invention are of a sufficiently low cost to allowdisposal after either a single use or a limited number of uses. Byproviding a disposable cleaning sheet it is possible to avoid problemsassociated with permanent or multi-use absorbent products such as, forexample, cross-contamination and the formation of bad odors, mildew,mold, etc.

[0126] The cleaning sheets can be provided dry or pre-moistened. In oneaspect, dry cleaning sheets can be provided with solid cleaning ordisinfecting agents coated on or in the sheets. In addition, thecleaning sheets can be provided in a pre-moistened condition. Thepre-moistened of the present invention contain the dual texture nonwovenweb of the present invention and a liquid which partially or fullysaturates the coform material. The wet cleaning sheets can be maintainedover time in a sealable container such as, for example, within a bucketwith an attachable lid, sealable plastic pouches or bags, canisters,jars, tubs and so forth. Desirably the wet, stacked cleaning sheets aremaintained in a resealable container. The use of a resealable containeris particularly desirable when using volatile liquid compositions sincesubstantial amounts of liquid can evaporate while using the first sheetsthereby leaving the remaining sheets with little or no liquid. Exemplaryresealable containers and dispensers include, but are not limited to,those described in U.S. Pat. No. 4,171,047 to Doyle et al., U.S. Pat.No. 4,353,480 to McFadden, U.S. Pat. No. 4,778,048 to Kaspar et al.,U.S. Pat. No. 4,741,944 to Jackson et al., U.S. Pat. No. 5,595,786 toMcBride et al.; the entire contents of each of the aforesaid referencesare incorporated herein by reference. The cleaning sheets can beincorporated or oriented in the container as desired and/or folded asdesired in order to improve ease of use or removal as is known in theart. Such folded configurations are well known to those skilled in theart and include c-folded, z-folded, quarter-folded configurations andthe like. The stack of folded wet wipes may be placed in the interior ofa container, such as a plastic tub, to provide a package of wet wipesfor eventual sale to the consumer. Alternatively, the wet wipes mayinclude a continuous strip of material which has perforations betweeneach wipe and which may be arranged in a stack or wound into a roll fordispensing.

[0127] With regard to pre-moistened sheets, a selected amount of liquidis added to the container such that the cleaning sheets contain thedesired amount of liquid. Typically, the cleaning sheets are stacked andplaced in the container and the liquid subsequently added thereto. Thesheet can subsequently be used to wipe a surface as well as act as avehicle to deliver and apply cleaning liquids to a surface. Themoistened and/or saturated cleaning sheets can be used to treat varioussurfaces. As used herein “treating” surfaces is used in the broad senseand includes, but is not limited to, wiping, polishing, swabbing,cleaning, washing, disinfecting, scrubbing, scouring, sanitizing, and/orapplying active agents thereto. The amount and composition of the liquidadded to the cleaning sheets will vary with the desired applicationand/or function of the wipes. As used herein the term “liquid” includes,but is not limited to, solutions, emulsions, suspensions and so forth.Thus, liquids may comprise and/or contain one or more of the following:disinfectants; antiseptics; diluents; surfactants, such as nonionic,anionic, cationic, waxes; antimicrobial agents; sterilants; sporicides;germicides; bactericides; fungicides; virucides; protozoacides;algicides; bacteriostats; fungistats; virustats; sanitizers;antibiotics; pesticides; and so forth. Numerous cleaning compositionsand compounds are known in the art and can be used in connection withthe present invention. The liquid may also contain lotions and/ormedicaments. The present invention also relates to new cleaning sheetswhich have an abrasive scrubbing surface while maintaining adequatestrength and resiliency. The premoistened cleaning sheets of the presentinvention can be used for, hand wipes, face wipes, cosmetic wipes,household wipes, industrial wipes and the like.

[0128] The amount of liquid contained within each premoistened cleaningsheet may vary depending upon the type of material being used to providethe pre-moistened cleaning sheet, the type of liquid being used, thetype of container being used to store the wet wipes, and the desired enduse of the wet wipe. Generally, each pre-moistened cleaning sheet cancontain from about 150 to about 900 weight percent, depending on the enduse.

[0129] For example, for a low lint countertop or glass wipe a saturationlevel of about 150 to about 650 weight percent is desirable. For apre-saturated mop application, the saturation level is desirably fromabout 500 to about 900 weight percent liquid based on the dry weight ofthe cleaning sheet, preferably about 650 to about 800 weight percent. Ifthe amount of liquid is less than the above-identified ranges, thecleaning sheet may be too dry and may not adequately perform. If theamount of liquid is greater than the above-identified ranges, thecleaning sheet may be oversaturated and soggy and the liquid may pool inthe bottom of the container.

[0130] The cleaning sheets of the present invention can be provided in akit form, wherein a plurality of cleaning sheets and a cleaning tool areprovided in a single package.

[0131] It has been discovered that the coform materials of the presentinvention have overall better wiping properties than prior dual texturewipes. Prior dual texture wipes would tend to “skate” across a surfaceto be cleaned, often leaving streaks in the cleaned surface when acleaning solution was used. It has been discovered that the dual texturecoform material of the present invention does not tend to streak whileproviding an abrasive cleaning surface.

EXAMPLES Example 1

[0132] Using the process described in FIG. 2, on a polypropylenespunbond nonwoven fabric having a basis weight of 14 gsm a first coformlayer is formed. The first layer of coform is a fine coform layercomprises 70% by weight pulp (Golden Isles 4824, available fromGeorgia-Pacific) and 30% by weight polypropylene (PF-015 available fromBasell) and has a fine fiber diameter of about 4 microns. Thepolypropylene was meltblown at a rate of about six (6) pounds per hour,through a die having 30 orifices per inch and having an average orificediameter of about 0.0145 inches, at a primary air temperature of 515°F., using a primary air flow rates of about 330 cfm (cubic feet perminute) A coarse coform layer comprising 40% by weight pulp (GoldenIsles 4824, available from Georgia-Pacific) and 60% by weightpolypropylene (PF-015 available from Basell) is then formed on the finecoform layer wherein the coarse fiber layer has an average fiberdiameter of about 28 microns. The polypropylene for the coarse fiberlayer was meltblown at a rate of about 12 pounds per hour, through a diehaving 30 orifices per inch an having an average orifice diameter ofabout 0.0145 inches, at a primary air temperature of about 460° F.,using a primary air flow rates of about 250 cfm. The resulting dualtexture coform nonwoven fabric has a basis weight of about 116 gsm,including the spunbond layer and any moisture. FIG. 4 is a micrographshowing the structure of the coform material prepared in this example.

Comparative Example 1

[0133] Using the process describe in FIG. 2 above, on a polypropylenespunbond nonwoven fabric having a basis weight of 14 gsm a first coformlayer is formed. The first coform layer is a fine coform layer comprises50% by weight pulp (Golden Isles 4824, available from Georgia-Pacific)and 50% by weight polypropylene (PF-015 available from Basell) and has afine fiber diameter of about 4 microns. The polypropylene was meltblownat a rate of about ten (10) pounds per hour, through a die having 30orifices per inch and having an average orifice diameter of about 0.0145inches, at a temperature of 480° F., using a primary air flow rates ofabout 330 cfm. A second fine meltblown fiber layer of coform comprising50% by weight pulp (Golden Isles 4824, available from Georgia-Pacific)and 50% by weight polypropylene (PF-015 available from Basell) is thenformed on the fine coform layer under the same conditions as the firstlayer. The resulting single texture coform nonwoven fabric has a basisweight of about 116 gsm, including the spunbond layer and any moisture.

Procedure for Testing Cleaning Efficiency of Wipers

[0134] Equipment needed: Vinyl flooring tiles affixed to ½″ plywoodbacking

[0135] Plastic template with 0.25″-diameter hole

[0136] 1-lb block with clamps which is 3 inches by 4 inches,

[0137] Two 2″-diameter string loops

[0138] Spatula

[0139] 1) The food was place on the template next to the hole. Thetemplate was firmly pressed against the vinyl flooring, and the food wasscraped over the hole using a spatula. Good contact between the spatulaand template was maintained to get a uniform surface of food that wasflush with the template upper surface. This process was repeated severaltimes to ensure that no voids or irregularities were present. The foodwas allowed to dry overnight for approximately 15 hours. The resultingfood stain had a diameter of about 0.25 inches in diameter and athickness of about 0.016 inches.

[0140] 2) The wipers were prepared by cutting to 3″×7″, and saturatingto 75% of the fabric's liquid capacity with a cleaning liquid (Pledge™Grab-it™ Wet Cleaning fluid). The wipers were placed in an air-tightplastic container to allow equilibration of the wipers.

[0141] 3) The wet wiper was applied to the 1-lb block. The block nextwas placed next to the dried food stain, oriented to be pulled over thestain in the block's long direction. Next, the string loops wereattached to the clamp hooks. The block assembly with the wiper attachedwas pulled over the food stain, back and forth, counting each pass overthe stain, until the stain is no longer visible. The number of passesrequired to remove the stain was recorded.

[0142] The results were recorded for each wipe prepared above and for acommercially available wipe. This test was repeated for 10 samples eachand the results are shown in Table 1. TABLE 1 Average Number of Wipes toRemove Stain Food Stain Example 1 Comp. Example 1 Swiffer Wet ™¹ Ketchup6.5 8.8 9.2

[0143] Using a Gardner Wet Abrasion Scrub Tester (Cat. No. 5000), theability of the dual texture coform material of the present invention toclean a surface is compared to the material of Comparative Example 1 andanother commercially available material. The Tester was modified byremoving the brushes and filling the cavities with LUCITE® blocks.Clamps held 2.25 in. (5.7 cm) by 8 in. (20.3 cm) samples of eachmaterial to the sleds of the Tester. A pressure of about 0.10 psi (3.9g/cm²) was applied to each wipe as it is passed across the food stain.

[0144] Chocolate or vanilla pudding samples were placed on white Delrin®polyacetal resin sheets or black Cobex/Leneta plastic panels,respectively. The pudding was placed on the template, which is describedabove, next to the hole. The template was firmly pressed against theglass panel, and the pudding was scraped over the hole using a spatula.Good contact between the spatula and template was maintained to get auniform surface of pudding that was flush with the template uppersurface. This process was repeated several times to ensure that no voidsor irregularities were present. The pudding was allowed to dry overnightfor approximately 15 hours. The resulting pudding stain had a diameterof about 0.25 inches in diameter and a thickness of about 0.016 inches.

[0145] The panels having the dried pudding stain were placed into theTester. The sled was allowed to pass back and forth over the stain untilthe stain was no longer visible. The number of cycles (back and forthmotion) required to remove the stain was recorded. This test wasrepeated for 10 samples and the results are shown in Table 2. TABLE 2Average Number of Wipes to Remove Stain Food Stain Example 1 Comp.Example 1 Swiffer Wet ™¹ Vanilla pudding 6.0 (σ = .47) 7.1 (σ = 1.3) 6.3(σ = .67) Chocolate pudding 6.2 (σ = .67) 6.8 (σ = .44) 7.0 (σ = 1.0)

[0146] As can be seen in Tables 1 and 2, the coform nonwoven web of thepresent invention has superior wiping properties as compared to a coformmaterial not having the coarse meltblown thermoplastic filaments andother commercially available wipes/mops.

[0147] While the invention has been described in detail with respect tospecific embodiments thereof, and particularly by the example describedherein, it will be apparent to those skilled in the art that variousalterations, modifications and other changes may be made withoutdeparting from the spirit and scope of the present invention. It istherefore intended that all such modifications, alterations and otherchanges be encompassed by the claims.

We claim:
 1. A dual texture coform nonwoven web comprising a matrix ofthermoplastic meltblown filaments and at least one secondary material,wherein the coform nonwoven web has a first exterior surface and asecond exterior surface, the first exterior surface comprises finethermoplastic meltblown fibers having an average diameter of less thanabout 15 microns and the secondary material; and the second exteriorsurface comprises coarse thermoplastic meltblown fibers having anaverage diameter greater than about 15 microns and the secondarymaterial.
 2. The dual texture coform of claim 1, wherein theconcentration of the coarse thermoplastic meltblown filaments in thematrix decrease in a direction from the second exterior surface towardsthe first exterior surface.
 3. The dual texture coform of claim 2,wherein the secondary material comprises an absorbent material selectedfrom the group consisting of absorbent particles, absorbent fibers and amixture of absorbent fibers and absorbent particles.
 4. The dual texturecoform of claim 3, wherein the absorbent material comprises pulp.
 5. Thedual texture coform of claim 2, wherein the coarse thermoplasticmeltblown filaments have an average fiber diameter in the range aboveabout 15 microns and less than about 39 microns.
 6. The dual texturecoform of claim 5, wherein the coarse thermoplastic meltblown fibershave an average fiber diameter in the range above about 20 microns andless than about 35 microns.
 7. The dual texture coform of claim 5,wherein the secondary material comprises an absorbent material selectedfrom the group consisting of absorbent particles, absorbent fibers and amixture of absorbent fibers and absorbent particles.
 8. The dual texturecoform of claim 7, wherein the absorbent material comprises pulp.
 9. Thedual texture coform of claim 3, wherein the absorbent material comprisesbetween about 20% and about 85% by weight of the coform material. 10.The dual texture coform of claim 9, wherein the absorbent materialcomprises between about 30% and about 70% by weight of the coformmaterial.
 11. The dual texture coform of claim 2, wherein the fine andcoarse thermoplastic meltblown filaments independently comprise apolymer selected from the group consisting of polyolefins, polyesters,polyamides, polycarbonates, polyurethanes, polyvinylchloride,polytetrafluoroethylene, polystyrene, polyethylene terephathalate,polylactic acid and copolymers and blends thereof.
 12. The dual texturecoform of claim 11, wherein the fine and coarse thermoplastic meltblownfilaments comprise a polyolefin selected from the group consisting ofpolyethylene, polypropylene, polybutylene and blends thereof.
 13. Thedual texture coform of claim 3, wherein the fine and coarsethermoplastic meltblown filaments comprise a polyolefin selected fromthe group consisting of polyethylene, polypropylene, polybutylene andblends thereof; the coarse thermoplastic meltblown filaments have anaverage fiber diameter in the range above about 15 microns and less thanabout 39 microns; the absorbent material comprises pulp and is presentin an amount of about 30% to about 70% by weight of the coform material.14. The dual texture coform of claim 13, wherein the fine and coarsethermoplastic meltblown filaments comprise polypropylene.
 15. A wipercomprising the dual texture coform nonwoven web of claim
 1. 16. Thewiper of claim 15, wherein the wiper is saturated with between about 150and about 900 weight percent of a liquid, based on the dry weight of thewipe.
 17. A wiper comprising the dual texture coform nonwoven web ofclaim
 14. 18. A mop comprising the dual texture coform nonwoven web ofclaim
 1. 19. The mop of claim 18, wherein the mop is saturated withbetween about 500 and about 900 weight percent of a liquid, based on thedry weight of the mop.
 20. A mop comprising the dual texture coformnonwoven web of claim
 14. 21. A dual texture nonwoven web comprising afirst surface and a second surface, wherein the first surface comprisesa composite matrix comprising fine thermoplastic meltblown filamentshaving an average diameter of less than about 15 microns and at leastone secondary material, and the second surface comprises a compositematrix comprising coarse thermoplastic meltblown fibers having anaverage diameter greater than about 15 microns and at least onesecondary material.
 22. The dual texture nonwoven web of claim 21,wherein the coarse thermoplastic meltblown fibers have an average fiberdiameter in the range above about 15 microns and less than about 39microns.
 23. The dual texture nonwoven web of claim 22, wherein thecoarse thermoplastic meltblown fibers have an average fiber diameter inthe range above about 20 microns and less than about 35 microns.
 24. Thedual texture nonwoven web of claim 21, wherein the secondary materialcomprises and absorbent material selected from the group consisting ofabsorbent particles, absorbent fibers and a mixture of absorbent fibersand absorbent particles.
 25. The dual texture nonwoven web of claim 24,wherein the absorbent material comprises pulp.
 26. The dual texturenonwoven web of claim 24, wherein the absorbent material comprisesbetween about 20% and about 85% by weight of the composite material. 27.The dual texture nonwoven web of claim 26, wherein the absorbentmaterial comprises between about 30% and about 70% by weight of thecomposite material.
 28. The dual texture nonwoven web of claim 21,wherein the fine and coarse thermoplastic meltblown filamentsindependently comprise a polymer selected from the group consisting ofpolyolefins, polyesters, polyamides, polycarbonates, polyurethanes,polyvinylchloride, polytetrafluoroethylene, polystyrene, polyethyleneterephathalate, polylactic acid and copolymers and blends thereof. 29.The dual texture nonwoven web of claim 28, wherein the fine and coarsethermoplastic meltblown filaments comprise a polyolefin selected fromthe group consisting of polyethylene, polypropylene, polybutylene andblends thereof.
 30. The dual texture coform of claim 24, wherein thefine and coarse thermoplastic meltblown filaments comprise a polyolefinselected from the group consisting of polyethylene, polypropylene,polybutylene and blends thereof; the coarse thermoplastic meltblownfilaments have an average fiber diameter in the range above about 15microns and less than about 39 microns; the absorbent material comprisespulp and is present in an amount of about 30% to about 70% by weight ofthe coform material.
 31. The dual texture coform nonwoven web of claim21, wherein the first surface further comprises coarse thermoplasticmeltblown fibers having an average diameter greater than about 15microns, and the second surface further comprises fine thermoplasticmeltblown filaments having an average diameter of less than about 15microns.
 32. A wiper comprising the dual texture nonwoven web of claim21.
 33. The wiper of claim 32, wherein the wiper is saturated withbetween about 150 and about 900 weight percent of a liquid, based on thedry weight of the wipe.
 34. A mop comprising the dual texture nonwovenweb of claim
 21. 35. The mop of claim 34, wherein the mop is saturatedwith between about 500 and about 900 weight percent of a liquid, basedon the dry weight of the mop.
 36. A method for preparing a dual texturecoform nonwoven web comprising a. providing a first stream ofthermoplastic meltblown filaments comprising filaments having an averagediameter of less than about 15 microns; b. providing a second stream ofthermoplastic meltblown filaments comprising filaments having an averagediameter greater than about 15 microns: c. converging the first streamof thermoplastic meltblown filaments and the second stream ofthermoplastic meltblown filaments in an intersecting relationship toform an impingement zone; d. introducing a stream of at least onesecondary material between the first and second streams of thethermoplastic meltblown filaments at or near the impingement zone toform a composite stream; and e. depositing the composite stream onto aforming surface as a matrix of meltblown filaments and a secondarymaterial to form a nonwoven web comprising a first and a second exteriorsurface; the first exterior surface comprises fine thermoplasticmeltblown fibers having average diameter of less than about 15 micronsand at least one secondary material, and the second exterior surfacecomprises coarse thermoplastic meltblown fibers having an averagediameter greater than about 15 microns and at least one secondarymaterial.
 37. A method for preparing a dual texture coform nonwoven webcomprising a. providing a first stream of thermoplastic meltblownfilaments; b. introducing a stream of at least one secondary material tothe first stream of thermoplastic meltblown filaments to form a firstcomposite stream; c. providing a second stream of thermoplasticmeltblown filaments; d. introducing a stream of at least one secondarymaterial to the first stream of thermoplastic meltblown filaments toform a second composite stream; e. depositing the first composite streamonto a forming surface as a matrix of thermoplastic meltblown filamentsand at least one secondary material to form a first deposited layer; andf. depositing the second composite stream onto the first deposited layeras a matrix of thermoplastic meltblown filaments and at least onesecondary material to form a dual texture coform nonwoven web; whereinone of the first stream of thermoplastic meltblown filaments or thesecond stream of thermoplastic meltblown filaments comprisesthermoplastic meltblown filaments having average diameter of less thanabout 15 microns and the other of the first stream of thermoplasticmeltblown fibers or the second stream of thermoplastic meltblown fiberscomprises thermoplastic meltblown filaments having an average diametergreater than about 15 microns.
 38. A cleaning implement comprising: a. ahandle; b. a head; and c. a removable cleaning sheet; wherein head isconnected to the handle, the removable cleaning sheet is removableattached to the head and the removable cleaning sheet comprises the dualtexture nonwoven web of claim
 1. 39. A cleaning implement comprising: a.a handle; b. a head; and c. a removable cleaning sheet; wherein head isconnected to the handle, the removable cleaning sheet is removableattached to the head and the removable cleaning sheet comprises the dualtexture nonwoven web of claim
 21. 40. A method of cleaning a surfacecomprising contacting and wiping the surface with a cleaning sheetcomprising the dual texture nonwoven web of claim
 1. 41. A method ofcleaning a surface comprising contacting and wiping the surface with acleaning sheet comprising the dual texture nonwoven web of claim
 21. 42.A kit comprising the cleaning implement of claim 38 and a plurality ofthe dual texture nonwoven webs.
 43. A kit comprising the cleaningimplement of claim 39 and a plurality of the dual texture nonwoven webs.